1. Field of the Invention
The present invention relates to a multiband orthogonal frequency division multiplexing alliance (MBOA) medium access control (MAC) based wireless communication, and more particularly, a wireless universal serial bus (WUSB).
2. Description of Related Art
A universal serial bus (USB) is one of the most successful connecting methods in personal computer (PC) history, and numerous USB devices are currently used. As the USB has been continuously developed, the USB is widely used with PCs, PC peripherals, consumer devices, and mobile communication devices. Standardization and details of the USB are supported by a universal serial bus implementers forum (USB-IF).
Wireless universal serial bus (WUSB) is a technology combining USB technology with future wireless technology based on the success of the wired USB. The WUSB is applicable to the PC, the PC peripheral, the consumer device, and the mobile communication device like the wired USB. In order to maintain an identical usage model and a configuration of wired USB 2.0, the WUSB standard defines a high-speed host device. Accordingly, the WUSB standard may incorporate aspects from current wired USB solutions.
In order to support the development of the best solutions for a market emergence of ultra wideband (UWB) based technology, a multiband orthogonal frequency division multiplexing alliance (MBOA) was founded in June 2003, and comprised of over 170 member companies. The member companies originally suggested a UWB standard based on orthogonal frequency division multiplexing (OFDM) technology as Texas Instruments (TI) had proposed in March 2003. The UWB standard supports the most widely applied fields, and facilitates a regulatory approval process.
A WiMedia Alliance and a multiband orthogonal frequency division multiplexing alliance special interest group (MBOA-SIG) were combined into an organization in March 2005. The organization was named WiMedia Alliance, Inc. and continues to promote adoption and standardization of the UWB for high-speed wireless communication and multimedia-capable personal-area connectivity.
The WiMedia Alliance completed the standardization of a multiband orthogonal frequency division multiplexing alliance medium access control (MBOA MAC) and released the standardized MBOA MAC to MBOA-SIG members. Accordingly, many applications such as the WUSB, wireless. 1394, and wireless IP are operated based on the MBOA MAC.
FIG. 1 is a diagram illustrating a WUSB network according to the conventional art.
Referring to FIG. 1, the WUSB network according to the conventional art includes a WUSB host 110, and a WUSB client 120.
A relationship between the WUSB host 110 and the WUSB client 120 is a star topology where each device directly connected. As illustrated in FIG. 1, one WUSB host and a plurality of WUSB devices indicates a cluster.
The WUSB host 110 may logically connect up to 127 devices, transmit data to and receive data from devices in the cluster, and perform scheduling. Also, the WUSB host 110 assigns a time slot and a band to each of the connected devices. The clusters may be piled up with minimum interference in a spatial environment. Accordingly, many WUSB clusters may exist together in a same wireless cell.
Various wireless WUSB apparatuses comprising a home network, etc. may form at least two WUSB clusters. For example, there is a WUSB cluster in which a digital television (DTV) operates as a host, and a WUSB cluster in which a portable multimedia player (PMP) operates as a host around the DTV. In this case, a WUSB apparatus which operates as a host in one cluster might not operate as a host in another cluster in the conventional art. Namely, the PMP which operates as a host in one cluster might not be connected to the DTV as a WUSB device while operating as the host, in the conventional art.
Accordingly, while operating as a host in one cluster, a new WUSB apparatus enabling a connection to a host in another neighboring cluster and operating as a device is highly required.